1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                                N A M E T                                 --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2020, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
17-- for  more details.  You should have  received  a copy of the GNU General --
18-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
19-- http://www.gnu.org/licenses for a complete copy of the license.          --
20--                                                                          --
21-- GNAT was originally developed  by the GNAT team at  New York University. --
22-- Extensive contributions were provided by Ada Core Technologies Inc.      --
23--                                                                          --
24------------------------------------------------------------------------------
25
26with Alloc;
27with Hostparm; use Hostparm;
28with Table;
29with Types;    use Types;
30
31package Namet is
32
33--  WARNING: There is a C version of this package. Any changes to this
34--  source file must be properly reflected in the C header file namet.h
35
36--  This package contains routines for handling the names table. The table
37--  is used to store character strings for identifiers and operator symbols,
38--  as well as other string values such as unit names and file names.
39
40--  The forms of the entries are as follows:
41
42--    Identifiers        Stored with upper case letters folded to lower case.
43--                       Upper half (16#80# bit set) and wide characters are
44--                       stored in an encoded form (Uhh for upper half char,
45--                       Whhhh for wide characters, WWhhhhhhhh as provided by
46--                       the routine Append_Encoded, where hh are hex
47--                       digits for the character code using lower case a-f).
48--                       Normally the use of U or W in other internal names is
49--                       avoided, but these letters may be used in internal
50--                       names (without this special meaning), if they appear
51--                       as the last character of the name, or they are
52--                       followed by an upper case letter (other than the WW
53--                       sequence), or an underscore.
54
55--    Operator symbols   Stored with an initial letter O, and the remainder
56--                       of the name is the lower case characters XXX where
57--                       the name is Name_Op_XXX, see Snames spec for a full
58--                       list of the operator names. Normally the use of O
59--                       in other internal names is avoided, but it may be
60--                       used in internal names (without this special meaning)
61--                       if it is the last character of the name, or if it is
62--                       followed by an upper case letter or an underscore.
63
64--    Character literals Character literals have names that are used only for
65--                       debugging and error message purposes. The form is an
66--                       upper case Q followed by a single lower case letter,
67--                       or by a Uxx/Wxxxx/WWxxxxxxx encoding as described for
68--                       identifiers. The Set_Character_Literal_Name procedure
69--                       should be used to construct these encodings. Normally
70--                       the use of O in other internal names is avoided, but
71--                       it may be used in internal names (without this special
72--                       meaning) if it is the last character of the name, or
73--                       if it is followed by an upper case letter or an
74--                       underscore.
75
76--    Unit names         Stored with upper case letters folded to lower case,
77--                       using Uhh/Whhhh/WWhhhhhhhh encoding as described for
78--                       identifiers, and a %s or %b suffix for specs/bodies.
79--                       See package Uname for further details.
80
81--    File names         Are stored in the form provided by Osint. Typically
82--                       they may include wide character escape sequences and
83--                       upper case characters (in non-encoded form). Casing
84--                       is also derived from the external environment. Note
85--                       that file names provided by Osint must generally be
86--                       consistent with the names from Fname.Get_File_Name.
87
88--    Other strings      The names table is also used as a convenient storage
89--                       location for other variable length strings such as
90--                       error messages etc. There are no restrictions on what
91--                       characters may appear for such entries.
92
93--  Note: the encodings Uhh (upper half characters), Whhhh (wide characters),
94--  WWhhhhhhhh (wide wide characters) and Qx (character literal names) are
95--  described in the spec, since they are visible throughout the system (e.g.
96--  in debugging output). However, no code should depend on these particular
97--  encodings, so it should be possible to change the encodings by making
98--  changes only to the Namet specification (to change these comments) and the
99--  body (which actually implements the encodings).
100
101--  The names are hashed so that a given name appears only once in the table,
102--  except that names entered with Name_Enter as opposed to Name_Find are
103--  omitted from the hash table.
104
105--  The first 26 entries in the names table (with Name_Id values in the range
106--  First_Name_Id .. First_Name_Id + 25) represent names which are the one
107--  character lower case letters in the range a-z, and these names are created
108--  and initialized by the Initialize procedure.
109
110--  Five values, one of type Int, one of type Byte, and three of type Boolean,
111--  are stored with each names table entry and subprograms are provided for
112--  setting and retrieving these associated values. The usage of these values
113--  is up to the client:
114
115--    In the compiler we have the following uses:
116
117--      The Int field is used to point to a chain of potentially visible
118--      entities (see Sem.Ch8 for details).
119
120--      The Byte field is used to hold the Token_Type value for reserved words
121--      (see Sem for details).
122
123--      The Boolean1 field is used to mark address clauses to optimize the
124--      performance of the Exp_Util.Following_Address_Clause function.
125
126--      The Boolean2 field is used to mark simple names that appear in
127--      Restriction[_Warning]s pragmas for No_Use_Of_Entity. This avoids most
128--      unnecessary searches of the No_Use_Of_Entity table.
129
130--      The Boolean3 field is set for names of pragmas that are to be ignored
131--      because of the occurrence of a corresponding pragma Ignore_Pragma.
132
133--    In the binder, we have the following uses:
134
135--      The Int field is used in various ways depending on the name involved,
136--      see binder documentation for details.
137
138--      The Byte and Boolean fields are unused.
139
140--  Note that the value of the Int and Byte fields are initialized to zero,
141--  and the Boolean field is initialized to False, when a new Name table entry
142--  is created.
143
144   type Bounded_String (Max_Length : Natural := 2**12) is limited
145   --  It's unlikely to have names longer than this. But we don't want to make
146   --  it too big, because we declare these on the stack in recursive routines.
147   record
148      Length : Natural := 0;
149      Chars  : String (1 .. Max_Length);
150   end record;
151
152   --  To create a Name_Id, you can declare a Bounded_String as a local
153   --  variable, and Append things onto it, and finally call Name_Find.
154   --  You can also use a String, as in:
155   --     X := Name_Find (Some_String & "_some_suffix");
156
157   --  For historical reasons, we also have the Global_Name_Buffer below,
158   --  which is used by most of the code via the renamings. New code ought
159   --  to avoid the global.
160
161   Global_Name_Buffer : Bounded_String (Max_Length => 4 * Max_Line_Length);
162   Name_Buffer        : String renames Global_Name_Buffer.Chars;
163   Name_Len           : Natural renames Global_Name_Buffer.Length;
164
165   --  Note that there is some circuitry (e.g. Osint.Write_Program_Name) that
166   --  does a save/restore on Name_Len and Name_Buffer (1 .. Name_Len). This
167   --  works in part because Name_Len is default-initialized to 0.
168
169   -----------------------------
170   -- Types for Namet Package --
171   -----------------------------
172
173   --  Name_Id values are used to identify entries in the names table. Except
174   --  for the special values No_Name and Error_Name, they are subscript values
175   --  for the Names table defined in this package.
176
177   --  Note that with only a few exceptions, which are clearly documented, the
178   --  type Name_Id should be regarded as a private type. In particular it is
179   --  never appropriate to perform arithmetic operations using this type.
180
181   type Name_Id is range Names_Low_Bound .. Names_High_Bound;
182   for Name_Id'Size use 32;
183   --  Type used to identify entries in the names table
184
185   No_Name : constant Name_Id := Names_Low_Bound;
186   --  The special Name_Id value No_Name is used in the parser to indicate
187   --  a situation where no name is present (e.g. on a loop or block).
188
189   Error_Name : constant Name_Id := Names_Low_Bound + 1;
190   --  The special Name_Id value Error_Name is used in the parser to
191   --  indicate that some kind of error was encountered in scanning out
192   --  the relevant name, so it does not have a representable label.
193
194   First_Name_Id : constant Name_Id := Names_Low_Bound + 2;
195   --  Subscript of first entry in names table
196
197   subtype Valid_Name_Id is Name_Id range First_Name_Id .. Name_Id'Last;
198   --  All but No_Name and Error_Name
199
200   function Present (Nam : Name_Id) return Boolean;
201   pragma Inline (Present);
202   --  Determine whether name Nam exists
203
204   -----------------
205   -- Subprograms --
206   -----------------
207
208   function To_String (Buf : Bounded_String) return String;
209   pragma Inline (To_String);
210   function "+" (Buf : Bounded_String) return String renames To_String;
211
212   function Name_Find
213     (Buf : Bounded_String := Global_Name_Buffer) return Valid_Name_Id;
214   function Name_Find (S : String) return Valid_Name_Id;
215   --  Name_Find searches the names table to see if the string has already been
216   --  stored. If so, the Id of the existing entry is returned. Otherwise a new
217   --  entry is created with its Name_Table_Int fields set to zero/false. Note
218   --  that it is permissible for Buf.Length to be zero to lookup the empty
219   --  name string.
220
221   function Name_Enter
222     (Buf : Bounded_String := Global_Name_Buffer) return Valid_Name_Id;
223   function Name_Enter (S : String) return Valid_Name_Id;
224   --  Name_Enter is similar to Name_Find. The difference is that it does not
225   --  search the table for an existing match, and also subsequent Name_Find
226   --  calls using the same name will not locate the entry created by this
227   --  call. Thus multiple calls to Name_Enter with the same name will create
228   --  multiple entries in the name table with different Name_Id values. This
229   --  is useful in the case of created names, which are never expected to be
230   --  looked up. Note: Name_Enter should never be used for one character
231   --  names, since these are efficiently located without hashing by Name_Find
232   --  in any case.
233
234   function Name_Equals
235     (N1 : Valid_Name_Id;
236      N2 : Valid_Name_Id) return Boolean;
237   --  Return whether N1 and N2 denote the same character sequence
238
239   function Get_Name_String (Id : Valid_Name_Id) return String;
240   --  Returns the characters of Id as a String. The lower bound is 1.
241
242   --  The following Append procedures ignore any characters that don't fit in
243   --  Buf.
244
245   procedure Append (Buf : in out Bounded_String; C : Character);
246   --  Append C onto Buf
247   pragma Inline (Append);
248
249   procedure Append (Buf : in out Bounded_String; V : Nat);
250   --  Append decimal representation of V onto Buf
251
252   procedure Append (Buf : in out Bounded_String; S : String);
253   --  Append S onto Buf
254
255   procedure Append (Buf : in out Bounded_String; Buf2 : Bounded_String);
256   --  Append Buf2 onto Buf
257
258   procedure Append (Buf : in out Bounded_String; Id : Valid_Name_Id);
259   --  Append the characters of Id onto Buf. It is an error to call this with
260   --  one of the special name Id values (No_Name or Error_Name).
261
262   procedure Append_Decoded (Buf : in out Bounded_String; Id : Valid_Name_Id);
263   --  Same as Append, except that the result is decoded, so that upper half
264   --  characters and wide characters appear as originally found in the source
265   --  program text, operators have their source forms (special characters and
266   --  enclosed in quotes), and character literals appear surrounded by
267   --  apostrophes.
268
269   procedure Append_Decoded_With_Brackets
270     (Buf : in out Bounded_String;
271      Id  : Valid_Name_Id);
272   --  Same as Append_Decoded, except that the brackets notation (Uhh
273   --  replaced by ["hh"], Whhhh replaced by ["hhhh"], WWhhhhhhhh replaced by
274   --  ["hhhhhhhh"]) is used for all non-lower half characters, regardless of
275   --  how Opt.Wide_Character_Encoding_Method is set, and also in that
276   --  characters in the range 16#80# .. 16#FF# are converted to brackets
277   --  notation in all cases. This routine can be used when there is a
278   --  requirement for a canonical representation not affected by the
279   --  character set options (e.g. in the binder generation of symbols).
280
281   procedure Append_Unqualified
282     (Buf : in out Bounded_String; Id : Valid_Name_Id);
283   --  Same as Append, except that qualification (as defined in unit
284   --  Exp_Dbug) is removed (including both preceding __ delimited names, and
285   --  also the suffixes used to indicate package body entities and to
286   --  distinguish between overloaded entities). Note that names are not
287   --  qualified until just before the call to gigi, so this routine is only
288   --  needed by processing that occurs after gigi has been called.
289
290   procedure Append_Unqualified_Decoded
291     (Buf : in out Bounded_String;
292      Id  : Valid_Name_Id);
293   --  Same as Append_Unqualified, but decoded as for Append_Decoded
294
295   procedure Append_Encoded (Buf : in out Bounded_String; C : Char_Code);
296   --  Appends given character code at the end of Buf. Lower case letters and
297   --  digits are stored unchanged. Other 8-bit characters are stored using the
298   --  Uhh encoding (hh = hex code), other 16-bit wide character values are
299   --  stored using the Whhhh (hhhh = hex code) encoding, and other 32-bit wide
300   --  wide character values are stored using the WWhhhhhhhh (hhhhhhhh = hex
301   --  code). Note that this procedure does not fold upper case letters (they
302   --  are stored using the Uhh encoding).
303
304   procedure Set_Character_Literal_Name
305     (Buf : in out Bounded_String;
306      C   : Char_Code);
307   --  This procedure sets the proper encoded name for the character literal
308   --  for the given character code.
309
310   procedure Insert_Str
311     (Buf   : in out Bounded_String;
312      S     : String;
313      Index : Positive);
314   --  Inserts S in Buf, starting at Index. Any existing characters at or past
315   --  this location get moved beyond the inserted string.
316
317   function Is_Internal_Name (Buf : Bounded_String) return Boolean;
318
319   procedure Get_Last_Two_Chars
320     (N  : Valid_Name_Id;
321      C1 : out Character;
322      C2 : out Character);
323   --  Obtains last two characters of a name. C1 is last but one character and
324   --  C2 is last character. If name is less than two characters long then both
325   --  C1 and C2 are set to ASCII.NUL on return.
326
327   function Get_Name_Table_Boolean1 (Id : Valid_Name_Id) return Boolean;
328   function Get_Name_Table_Boolean2 (Id : Valid_Name_Id) return Boolean;
329   function Get_Name_Table_Boolean3 (Id : Valid_Name_Id) return Boolean;
330   --  Fetches the Boolean values associated with the given name
331
332   function Get_Name_Table_Byte (Id : Valid_Name_Id) return Byte;
333   pragma Inline (Get_Name_Table_Byte);
334   --  Fetches the Byte value associated with the given name
335
336   function Get_Name_Table_Int (Id : Valid_Name_Id) return Int;
337   pragma Inline (Get_Name_Table_Int);
338   --  Fetches the Int value associated with the given name
339
340   procedure Set_Name_Table_Boolean1 (Id : Valid_Name_Id; Val : Boolean);
341   procedure Set_Name_Table_Boolean2 (Id : Valid_Name_Id; Val : Boolean);
342   procedure Set_Name_Table_Boolean3 (Id : Valid_Name_Id; Val : Boolean);
343   --  Sets the Boolean value associated with the given name
344
345   procedure Set_Name_Table_Byte (Id : Valid_Name_Id; Val : Byte);
346   pragma Inline (Set_Name_Table_Byte);
347   --  Sets the Byte value associated with the given name
348
349   procedure Set_Name_Table_Int (Id : Valid_Name_Id; Val : Int);
350   pragma Inline (Set_Name_Table_Int);
351   --  Sets the Int value associated with the given name
352
353   function Is_Internal_Name (Id : Valid_Name_Id) return Boolean;
354   --  Returns True if the name is an internal name, i.e. contains a character
355   --  for which Is_OK_Internal_Letter is true, or if the name starts or ends
356   --  with an underscore.
357   --
358   --  Note: if the name is qualified (has a double underscore), then only the
359   --  final entity name is considered, not the qualifying names. Consider for
360   --  example that the name:
361   --
362   --    pkg__B_1__xyz
363   --
364   --  is not an internal name, because the B comes from the internal name of
365   --  a qualifying block, but the xyz means that this was indeed a declared
366   --  identifier called "xyz" within this block and there is nothing internal
367   --  about that name.
368
369   function Is_OK_Internal_Letter (C : Character) return Boolean;
370   pragma Inline (Is_OK_Internal_Letter);
371   --  Returns true if C is a suitable character for using as a prefix or a
372   --  suffix of an internally generated name, i.e. it is an upper case letter
373   --  other than one of the ones used for encoding source names (currently the
374   --  set of reserved letters is O, Q, U, W) and also returns False for the
375   --  letter X, which is reserved for debug output (see Exp_Dbug).
376
377   function Is_Operator_Name (Id : Valid_Name_Id) return Boolean;
378   --  Returns True if name given is of the form of an operator (that is, it
379   --  starts with an upper case O).
380
381   function Is_Valid_Name (Id : Name_Id) return Boolean;
382   --  True if Id is a valid name - points to a valid entry in the Name_Entries
383   --  table.
384
385   function Length_Of_Name (Id : Valid_Name_Id) return Nat;
386   pragma Inline (Length_Of_Name);
387   --  Returns length of given name in characters. This is the length of the
388   --  encoded name, as stored in the names table.
389
390   procedure Initialize;
391   --  This is a dummy procedure. It is retained for easy compatibility with
392   --  clients who used to call Initialize when this call was required. Now
393   --  initialization is performed automatically during package elaboration.
394   --  Note that this change fixes problems which existed prior to the change
395   --  of Initialize being called more than once. See also Reinitialize which
396   --  allows reinitialization of the tables.
397
398   procedure Reinitialize;
399   --  Clears the name tables and removes all existing entries from the table.
400
401   procedure Reset_Name_Table;
402   --  This procedure is used when there are multiple source files to reset the
403   --  name table info entries associated with current entries in the names
404   --  table. There is no harm in keeping the names entries themselves from one
405   --  compilation to another, but we can't keep the entity info, since this
406   --  refers to tree nodes, which are destroyed between each main source file.
407
408   procedure Finalize;
409   --  Called at the end of a use of the Namet package (before a subsequent
410   --  call to Initialize). Currently this routine is only used to generate
411   --  debugging output.
412
413   procedure Lock;
414   --  Lock name tables before calling back end. We reserve some extra space
415   --  before locking to avoid unnecessary inefficiencies when we unlock.
416
417   procedure Unlock;
418   --  Unlocks the name table to allow use of the extra space reserved by the
419   --  call to Lock. See gnat1drv for details of the need for this.
420
421   procedure Write_Name (Id : Valid_Name_Id);
422   --  Write_Name writes the characters of the specified name using the
423   --  standard output procedures in package Output. The name is written
424   --  in encoded form (i.e. including Uhh, Whhh, Qx, _op as they appear in
425   --  the name table). If Id is Error_Name, or No_Name, no text is output.
426
427   procedure Write_Name_Decoded (Id : Valid_Name_Id);
428   --  Like Write_Name, except that the name written is the decoded name, as
429   --  described for Append_Decoded.
430
431   function Name_Entries_Count return Nat;
432   --  Return current number of entries in the names table
433
434   function Last_Name_Id return Name_Id;
435   --  Return the last Name_Id in the table. This information is valid until
436   --  new names have been added.
437
438   --------------------------
439   -- Obsolete Subprograms --
440   --------------------------
441
442   --  The following routines operate on Global_Name_Buffer. New code should
443   --  use the routines above, and declare Bounded_Strings as local
444   --  variables. Existing code can be improved incrementally by removing calls
445   --  to the following. ???If we eliminate all of these, we can remove
446   --  Global_Name_Buffer. But be sure to look at namet.h first.
447
448   --  To see what these do, look at the bodies. They are all trivially defined
449   --  in terms of routines above.
450
451   procedure Add_Char_To_Name_Buffer (C : Character);
452   pragma Inline (Add_Char_To_Name_Buffer);
453
454   procedure Add_Nat_To_Name_Buffer (V : Nat);
455
456   procedure Add_Str_To_Name_Buffer (S : String);
457
458   procedure Get_Decoded_Name_String (Id : Valid_Name_Id);
459
460   procedure Get_Decoded_Name_String_With_Brackets (Id : Valid_Name_Id);
461
462   procedure Get_Name_String (Id : Valid_Name_Id);
463
464   procedure Get_Name_String_And_Append (Id : Valid_Name_Id);
465
466   procedure Get_Unqualified_Decoded_Name_String (Id : Valid_Name_Id);
467
468   procedure Get_Unqualified_Name_String (Id : Valid_Name_Id);
469
470   procedure Insert_Str_In_Name_Buffer (S : String; Index : Positive);
471
472   function Is_Internal_Name return Boolean;
473
474   procedure Set_Character_Literal_Name (C : Char_Code);
475
476   procedure Store_Encoded_Character (C : Char_Code);
477
478   ------------------------------
479   -- File and Unit Name Types --
480   ------------------------------
481
482   --  These are defined here in Namet rather than Fname and Uname to avoid
483   --  problems with dependencies, and to avoid dragging in Fname and Uname
484   --  into many more files, but it would be cleaner to move to Fname/Uname.
485
486   type File_Name_Type is new Name_Id;
487   --  File names are stored in the names table and this type is used to
488   --  indicate that a Name_Id value is being used to hold a simple file name
489   --  (which does not include any directory information).
490
491   No_File : constant File_Name_Type := File_Name_Type (No_Name);
492   --  Constant used to indicate no file is present (this is used for example
493   --  when a search for a file indicates that no file of the name exists).
494
495   function Present (Nam : File_Name_Type) return Boolean;
496   pragma Inline (Present);
497   --  Determine whether file name Nam exists
498
499   Error_File_Name : constant File_Name_Type := File_Name_Type (Error_Name);
500   --  The special File_Name_Type value Error_File_Name is used to indicate
501   --  a unit name where some previous processing has found an error.
502
503   subtype Error_File_Name_Or_No_File is
504     File_Name_Type range No_File .. Error_File_Name;
505   --  Used to test for either error file name or no file
506
507   type Path_Name_Type is new Name_Id;
508   --  Path names are stored in the names table and this type is used to
509   --  indicate that a Name_Id value is being used to hold a path name (that
510   --  may contain directory information).
511
512   No_Path : constant Path_Name_Type := Path_Name_Type (No_Name);
513   --  Constant used to indicate no path name is present
514
515   type Unit_Name_Type is new Name_Id;
516   --  Unit names are stored in the names table and this type is used to
517   --  indicate that a Name_Id value is being used to hold a unit name, which
518   --  terminates in %b for a body or %s for a spec.
519
520   No_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (No_Name);
521   --  Constant used to indicate no file name present
522
523   function Present (Nam : Unit_Name_Type) return Boolean;
524   pragma Inline (Present);
525   --  Determine whether unit name Nam exists
526
527   Error_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (Error_Name);
528   --  The special Unit_Name_Type value Error_Unit_Name is used to indicate
529   --  a unit name where some previous processing has found an error.
530
531   subtype Error_Unit_Name_Or_No_Unit_Name is
532     Unit_Name_Type range No_Unit_Name .. Error_Unit_Name;
533
534   ------------------------
535   -- Debugging Routines --
536   ------------------------
537
538   procedure wn (Id : Name_Id);
539   pragma Export (Ada, wn);
540   --  This routine is intended for debugging use only (i.e. it is intended to
541   --  be called from the debugger). It writes the characters of the specified
542   --  name using the standard output procedures in package Output, followed by
543   --  a new line. The name is written in encoded form (i.e. including Uhh,
544   --  Whhh, Qx, _op as they appear in the name table). If Id is Error_Name,
545   --  No_Name, or invalid an appropriate string is written (<Error_Name>,
546   --  <No_Name>, <invalid name>). Unlike Write_Name, this call does not affect
547   --  the contents of Name_Buffer or Name_Len.
548
549private
550
551   ---------------------------
552   -- Table Data Structures --
553   ---------------------------
554
555   --  The following declarations define the data structures used to store
556   --  names. The definitions are in the private part of the package spec,
557   --  rather than the body, since they are referenced directly by gigi.
558
559   --  This table stores the actual string names. Although logically there is
560   --  no need for a terminating character (since the length is stored in the
561   --  name entry table), we still store a NUL character at the end of every
562   --  name (for convenience in interfacing to the C world).
563
564   package Name_Chars is new Table.Table (
565     Table_Component_Type => Character,
566     Table_Index_Type     => Int,
567     Table_Low_Bound      => 0,
568     Table_Initial        => Alloc.Name_Chars_Initial,
569     Table_Increment      => Alloc.Name_Chars_Increment,
570     Table_Name           => "Name_Chars");
571
572   type Name_Entry is record
573      Name_Chars_Index : Int;
574      --  Starting location of characters in the Name_Chars table minus one
575      --  (i.e. pointer to character just before first character). The reason
576      --  for the bias of one is that indexes in Name_Buffer are one's origin,
577      --  so this avoids unnecessary adds and subtracts of 1.
578
579      Name_Len : Short;
580      --  Length of this name in characters
581
582      Byte_Info : Byte;
583      --  Byte value associated with this name
584
585      Boolean1_Info : Boolean;
586      Boolean2_Info : Boolean;
587      Boolean3_Info : Boolean;
588      --  Boolean values associated with the name
589
590      Name_Has_No_Encodings : Boolean;
591      --  This flag is set True if the name entry is known not to contain any
592      --  special character encodings. This is used to speed up repeated calls
593      --  to Append_Decoded. A value of False means that it is not known
594      --  whether the name contains any such encodings.
595
596      Hash_Link : Name_Id;
597      --  Link to next entry in names table for same hash code
598
599      Int_Info : Int;
600      --  Int Value associated with this name
601
602   end record;
603
604   for Name_Entry use record
605      Name_Chars_Index      at  0 range 0 .. 31;
606      Name_Len              at  4 range 0 .. 15;
607      Byte_Info             at  6 range 0 .. 7;
608      Boolean1_Info         at  7 range 0 .. 0;
609      Boolean2_Info         at  7 range 1 .. 1;
610      Boolean3_Info         at  7 range 2 .. 2;
611      Name_Has_No_Encodings at  7 range 3 .. 7;
612      Hash_Link             at  8 range 0 .. 31;
613      Int_Info              at 12 range 0 .. 31;
614   end record;
615
616   for Name_Entry'Size use 16 * 8;
617   --  This ensures that we did not leave out any fields
618
619   --  This is the table that is referenced by Valid_Name_Id entries.
620   --  It contains one entry for each unique name in the table.
621
622   package Name_Entries is new Table.Table (
623     Table_Component_Type => Name_Entry,
624     Table_Index_Type     => Valid_Name_Id'Base,
625     Table_Low_Bound      => First_Name_Id,
626     Table_Initial        => Alloc.Names_Initial,
627     Table_Increment      => Alloc.Names_Increment,
628     Table_Name           => "Name_Entries");
629
630end Namet;
631